Then I go to Rome and in Rome the physics was very inspiring. Fermi was very young, he was about five years older than I, and he had made a name for himself and was a full professor and was in addition a member of a new academy in Italy which gave him the... the title of 'Excellency'. And it was of course in the midst of the Fascist times and Fermi's lab where he was really only an appendix to that lab, with the main professor was Calvino who was a very good experimental physicist and a very sensible person, he let Fermi do whatever he liked in one wing of the laboratory. But the whole lab was on a hill right next to the Department of the Interior and from time to time there was a meeting of important people in the Department of the Interior. When that happened the access to the entire region was blocked to any civilians. Fermi didn't like that and so when he came to the guard post he said 'I have to get in. I am the driver to Excellency Fermi, and his Excellency would be very annoyed if I didn't... didn't come.' And so on that basis he was let in. He looked like a driver and the guards never found out that he was himself 'His Excellency'.

The late German-American physicist Hans Bethe once described himself as the H-bomb's midwife. He left Nazi Germany in 1933, after which he helped develop the first atomic bomb, won the Nobel Prize in Physics in 1967 for his contribution to the theory of nuclear reactions, advocated tighter controls over nuclear weapons and campaigned vigorously for the peaceful use of nuclear energy.

Silvan Sam Schweber is the Koret Professor of the History of Ideas and Professor of Physics at Brandeis University, and a Faculty Associate in the Department of the History of Science at Harvard University. He is the author of a history of the development of quantum electro mechanics, "QED and the men who made it", and has recently completed a biography of Hans Bethe and the history of nuclear weapons development, "In the Shadow of the Bomb: Oppenheimer, Bethe, and the Moral Responsibility of the Scientist" (Princeton University Press, 2000).